Infusion bag with integrated rinsing system

ABSTRACT

The invention relates to a medical bag which is intended for the infusion of a medicament by means of gravity. The inventive bag comprises: at least two compartments, namely a first compartment ( 1 ) containing a medicament in the form of a solution and a second compartment ( 2 ) containing a rinsing solution; and means for separating/communicating the compartments, which prevent the rinsing solution from automatically entering the medicament compartment except at the end of the infusion period. The rinsing solution ends the infusion, by rinsing the medicament bag and the infusion line, such as to prevent any risk of contamination or leakage of residual medicament from the bag or line.

BACKGROUND OF THE INVENTION

The present invention relates to the infusion of medication contained ina flexible bag, which flows into the veins of a patient via an infusionline, under the effect of gravity, the bag being suspended above thepatient.

More particularly, the invention relates to a bag for medical use forinfusing medication by gravity, comprising at least two compartments,one containing medication and the other containing a rinsing solution,and separation/communication means for automatically rinsing themedication bag and infusion line.

The invention is intended to solve, simply and inexpensively, two majorproblems encountered with this type of infusion, namely:

-   -   the loss of some of the medication: The infusion line has a        non-negligible volume, in particular in the case of small        infusion bags. The amount of medication remaining in the line        plus the residual amount contained in the bag is not infused        into the patient who thus does not receive the prescribed dose;    -   the risk of contamination due to the toxicity of the medication:        the medication infused may be extremely toxic or allergenic        (cancer medication, antibiotics, etc.) and there may be a risk        of contamination when the care personnel purges the air from the        perfusion line before connecting up to the patient or when        disconnecting the infusion line.

The solution to these two problems consists in rinsing the line beforeand after infusion and rinsing the bag after infusion using a harmless,inexpensive solution (isotonic sodium chloride for example).

DESCRIPTION OF THE PRIOR ART

Devices are already known which can at least partially rinse thebag/line, limiting medication loss and the risks for care personnel.

U.S. Pat. No. 5,242,392 describes an infusion system comprising achamber for a rinsing liquid connected to the infusion tubing betweenthe medication bag and the injection device and located lower than themedication bag. When the medication has been administered, the rinsingsolution rinses the infusion tubing and injection device automatically.

Patent FR 2 794 983 describes a closed-circuit infusion systemcomprising at least one medication bag and dispensing and infusionmeans, associated with a rinsing bag in such a way that the rinsingsolution can flow through the dispensing and infusion means, and alsoselection means allowing the medication and/or the rinsing solution toflow through the dispensing and infusion means.

Patent FR 2 306 711 describes an infusion device comprising at least twoinfusion containers suspended at different heights, whose tubes areconnected for example using a Y-shaped connection piece, and a valvedevice with two inlets whose operation is linked to the difference inheight between the infusion containers which causes a difference inheight between the columns of liquid.

Documents WO 92/11881, U.S. Pat. No. 4,512,764, WO 95/09020, EP 0 790064, U.S. Pat. No. 4,623,334 and WO 03/077974 describe infusion orinjection systems comprising devices for rinsing the infusion line orinjection system.

These devices do not provide a satisfactory solution to the problems ofsafety and effectiveness of the infusion systems:

-   -   If the bag contains air, it may be completely emptied but a        relatively large part of the infusion line will contain air and        the line cannot be rinsed since the air contained in the line        would be injected in the patient (risk of air embolism). The        presence of the nurse is therefore required before the end of        infusion in order to carry out rinsing at the exact moment when        the bag is completely emptied, before some of the line fills        with air.    -   If the bag does not contain air, it cannot be completely emptied        and the residual liquid contained in the bag will not be        injected into the patient. In this case, the line may be rinsed,        but not the bag.    -   In all cases, the intervention of the nurse is required,        entailing extra work.

SUMMARY OF THE INVENTION

The present invention is intended to improve the safety andeffectiveness of infusion systems by virtue of a device forautomatically rinsing the line and the bag after infusion, without thenurse's intervention.

The present invention relates to a bag for medical use for infusingmedication by gravity, comprising at least two compartments, onecontaining medication in the form of a solution and the other(s)containing a rinsing solution, and compartment separation/communicationmeans which allow the rinsing solution to enter the compartmentcontaining the medication automatically only after infusion. The rinsingsolution completes the infusion, rinsing the medication bag and theinfusion line, thus eliminating the risk of contamination and the lossof residual medication in the bag and that contained in the infusionline.

The basic principle of the invention consists in using the vacuumcreated in the medication bag at the end of infusion owing to the watercolumn height in the infusion line. This vacuum gradually increases atthe end of infusion, as the bag becomes flattened through a “siphon”effect. This vacuum can reach around −100 mb.

The rinsing liquid, which is at atmospheric pressure, is drawn into thecompartment containing the medication, which in turn is at a vacuumpressure with respect to atmospheric pressure.

The separation/communication means comprise a breakable device betweenthe compartment containing the medication and the compartment (one ofthe compartments) containing the solution and a device for ensuringautomatic communication between the compartment containing themedication and the compartment containing the solution or between thetwo compartments containing the solution.

The device for ensuring automatic communication between the compartmentsmay be a communication channel positioned above the level of the liquidin said compartments when the bag is suspended vertically.

As a variant, the device for ensuring automatic communication betweenthe compartments may be a pressure-threshold valve.

The compartment or compartments containing the rinsing solution maycomprise a narrow area towards the top of the bag.

DESCRIPTION OF THE DRAWINGS

The attached drawings illustrate the present invention in more detail.

FIG. 1 shows an infusion bag with two compartments comprising acommunication channel.

FIG. 2 shows an infusion bag with two compartments comprising apressure-threshold valve.

FIG. 3 is a cross section through the pressure-threshold valve of FIG. 2with integrated breakable device in the closed state.

FIG. 4 shows the same valve in the open state.

FIG. 5 shows an infusion bag with three compartments comprising acommunication channel.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

According to a first embodiment of the invention shown in FIG. 1, use ismade of a flexible infusion bag separated into two juxtaposedcompartments (1) and (2), one (1) of which contains the medication andthe other (2) the rinsing solution. Compartment (1) comprises an access(4) for filling the bag and connecting to the infusion line (10).Compartment (2) comprises a narrow area (9) at the top of the bag and anaccess (5) for filling said compartment. The two compartments areseparated by a substantially vertical wall (7) whose upper partcomprises a breakable device (3) designed to ensure the seal between thetwo compartments when it is intact and to allow communication betweenthe two compartments when it is broken by the nurse by mechanicalintervention on the outside of the bag. This device is imperativelyplaced above the level of the liquids when the bag is suspended.

Compartments (1) and (2) are filled without the addition of air. Saidcompartments comprise means (8) and (6) for preventing the flow path ofthe liquid from being sealed up completely when the bag flattens. Thesemeans (8) and (6) may consist for example of a “roughening” of thesurface of one of the faces of the bag or a thermoformed channel, whichaid the flow.

According to a second embodiment of the invention shown in FIG. 2, useis made of a flexible infusion bag separated into two superposedcompartments (1) and (2). The two compartments are separated by asubstantially horizontal wall (7) whose central part comprises abreakable device (3) broken by the nurse. In this embodiment, the flowof the rinsing solution from compartment (2) to compartment (1) istriggered by a pressure-threshold valve (11) as a function of thedifference in pressure between the compartments (1) and (2).

Compartment (1) comprises means (8) for preventing the flow path of theliquid from being sealed up completely when the bag flattens. Thesemeans (8) facilitate the flow between the communication orifice betweenthe two compartments and the access (4) to the infusion line (10).

According to a variant (not shown) of the bag of FIG. 1 or 2, use ismade of two separate bags instead of one bag with two compartments.

FIGS. 3 and 4 show an example of the pressure-threshold valve used inthe bag of FIG. 2.

The valve comprises two chambers (14) and (15) separated by an elastomermembrane (13). As shown in FIG. 3, the seal between the two chambers isensured by the membrane (13) being pretensioned on the annular sealingring (17). The chamber (14) is in communication with compartment (2)containing the rinsing solution via the openings (12). After thebreakable device (3) is broken, the chamber (15) is in communicationwith the compartment (1) containing the medication.

As shown in FIG. 4, when the pressure inside the chamber (15) becomesnegative with respect to the pressure in the chamber (14), the membrane(13) detaches from the annular sealing ring (17), thus allowing therinsing liquid contained in compartment (2) to flow into compartment (1)via the orifice (16).

According to a third embodiment of the invention shown in FIG. 5, use ismade of a flexible infusion bag separated into three juxtaposedcompartments, allowing rinsing at the beginning and end of infusion.Compartment (1) contains the medication and is separated fromcompartments (2) and (2 a) containing rinsing solution by asubstantially vertical wall (7) whose lower part comprises a breakabledevice (3) broken by the nurse.

Compartments (2) and (2 a) are separated by a wall (20) leaving apassage (18) at the top of the bag which prevents the transfer of thecontents from (2) into (2 a) and/or the contents from (2 a) into (2) ifthe bag is suspended vertically and if there is no difference inpressure between said compartments. Compartment (2 a) comprises anaccess (4) to the infusion line (10). The volume of compartment (2 a) isslightly greater than the volume of a standard infusion line (around 10milliliters).

The following examples illustrate how the infusion bags of the inventionare used.

Example 1 Bag with Two Juxtaposed Compartments (FIG. 1)

After the infusion line has been established, the nurse breaks thebreakable device (3) by mechanical intervention on the outside of theflexible bag, to place the compartments (1) and (2) in communicationwithout causing transfer since the pressure inside the two compartmentsis identical. When compartment (1) is practically empty, its wallscollapse. The pressure in compartment (1) then becomes negative withrespect to the pressure in compartment (2), which flattens, causing therinsing liquid to rise into the communication channel between the twocompartments. The rising liquid then empties into compartment (1), andthen into the infusion line, thus rinsing the medication out ofcompartment (1) and the line (10). The patient will thus receive all themedication and the nurse will handle an infusion line and a bag free oftoxic liquid.

Example 2 Bag with Two Superposed Compartments (FIG. 2)

The method of example 1 is followed, except that it is thepressure-threshold valve that allows the rinsing solution to flow intocompartment (1) when the pressure in this compartment becomes negativewith respect to the pressure in compartment (2).

Example 3 Bag with Three Juxtaposed Compartments (FIG. 5)

Once the bag has been connected up to the infusion line (10), theair-filled infusion line is in communication with compartment (2 a)which is full of rinsing solution. The nurse starts infusion as usualwith the contents of compartment (2 a). After this operation,compartment (2 a) is almost empty.

The nurse connects the line to the patient, then breaks the breakabledevice (3). Compartment (1) is then in communication with compartment (2a) and thus with the infusion line (10). The medication contained in (1)flows into compartment (2 a) until the heights of liquid in saidcompartments are equal.

When compartments (1) and (2 a) are almost empty, the walls collapse,causing the rinsing solution in compartment (2) to be sucked intocompartment (2 a). After the levels between compartments (1) and (2 a)have equaled out, which rinses the bottom of the compartment, therinsing solution flows into the perfusion line (10).

The description and figures illustrate various embodiments of thepresent invention. However, the invention is not limited to theembodiments described and shown but, on the contrary, encompasses allvariants.

1. A bag for medical use for infusing medication by gravity, comprising:at least a first compartment, a second compartment and a thirdcompartment, the first compartment configured to contain medication inthe form of a solution, the third compartment configured to contain afirst rinsing solution, and the second compartment configured to containa second rinsing solution, wherein the first compartment, the secondcompartment and the third compartment are juxtaposed, a firstseparation/communication portion that separates the first compartmentand the third compartment, wherein the first separation/communicationportion comprises a breakable device disposed between the first and thethird compartment and the breakable device is disposed at a bottom endof the first separation/communication portion when the bag is suspendedvertically, and a second separation/communication portion that separatesthe second compartment and the third compartment, wherein the secondseparation/communication portion comprises a communication channeldisposed at an end of the bag that is above the second compartment whenthe bag is suspended vertically, and an access port for an infusion linedisposed at a bottom portion of the third compartment when the bag issuspended vertically, wherein the breakable device preventscommunication between the first compartment and the third compartmentwhen not broken, and the breakable device allows communication betweenthe first compartment and the third compartment when broken, wherein ifthe breakable device is broken, the medication is capable of flowinginto the third compartment and flowing into the infusion line via thethird compartment, and wherein the second rinsing solution is capable offlowing into the third compartment via the communication channel andflowing into the infusion line, after the first compartment and thethird compartment are almost emptied, wherein the communication channelhas an output side disposed at a height that substantially prevents thesecond rinsing solution from entering the third compartment until afterthe first compartment and the third compartment are almost emptied ofthe medication solution, and wherein the second separation/communicationportion is configured to allow the second rinsing solution toautomatically flow into the third compartment via the communicationchannel when a pressure in the first compartment and the thirdcompartment becomes negative with respect to a pressure in the secondcompartment under a siphon effect created by a fluid column height inthe infusion line.
 2. The bag according to claim 1, wherein the secondcompartment comprises a narrow area at the top of the bag.
 3. The bagaccording to claim 1, further comprising means for preventing the flowpath of the second rinsing solution from being sealed completely whenthe bag flattens.
 4. The bag according to claim 3, wherein the means forpreventing the flow path of the second rinsing solution from beingsealed completely comprises a roughening of the surface of at least oneface of the bag.
 5. The bag according to claim 3, wherein said means forpreventing the flow path of the second rinsing solution from beingsealed completely comprises a thermoformed channel.
 6. The bag accordingto claim 1, wherein the bag is flexible.
 7. The bag according to claim1, wherein the first compartment and the third compartment are separatedby a substantially vertical wall.
 8. The bag according to claim 1,wherein the third compartment and the second compartment are separatedby a substantially vertical wall.